It is not certain how old the Serenity Prayer is or who really wrote it. It may date as far back as Boethius (500 A.D.) who was a philosopher. Before he was martyred by the Christians, he was in prison for a long time during which he wrote "Consolation of Philosophy."

Reinhold Niebuhr is often credited with writing the Serenity Prayer but he credited Friedrich Oetinger who was an 18th century theologian.

Some schools actually instruct therapists not to "insert their own personalities" into the counseling process and discourage them from sharing anything at all about themselves with counselees. Yet. I believe that it is possible to maintain a balance between over-involvement and being so objective that those we work with never see our "human" side.A. The benefits of "self-revelation" in the counseling process
There are many good reasons to share our own spiritual journeys with those we seek to help, especially if we ourselves have overcome an addiction to drugs and alcohol.

1) Formulate and stamp indelibly on your mind a mental picture of yourself as succeeding. Hold this picture tenaciously. Never permit it to fade. Your mind will seek to develop this picture. Never think of yourself as failing; never doubt the reality of the mental image. That is most dangerous, for the mind always tries to complete what it pictures. So always picture "success" no matter how badly things seem to be going at the moment.
2) Whenever a negative thought concerning your personal powers come to mind, deliberately voice a positive thought to cancel it out.